察言观色[cháyánguānsè]-examineaman'slanguageandobservehiscountenance;carefullytoweighupaperson'swordsandcloselywatchhisexpression;divesb.'sthoughtsfromwhathesaysandtheexpressiononhisface;observesb.'sspeechandbehavior;takeone'scuefromsb.'swordsandfacialexpressions;watchaperson'severymood;watchaperson'sexpressionsandweighhiswordscarefully;weighsb.'swordsandwatchhisexpression:

Ishallhavetowatchmystep.我必须察言观色把他防!